Knitting machine



March 20, 1934. R. H. ROBINSON KNITTING MACHINE Filed Oct. 10, 1931 sSheets-Sheet 1 March 20, 1934. RoBlNSON 1,951,842

KNITTING MACHINE Filed Oct. 10, 1931 3 Sheets-Sheet 2 IIVENTOR March 20,1934. R, H ROBINSON 1,951,842

KNITTING MACHINE Filed Oct. 10, 1931 s Sheets-Sheet 3 Patented Mar. 20,1934 UNITED STATES PATENT OFFICE 1,951,842 KNITTING MACHINE ApplicationOctober. 10,

1931, Serial No. 568,059

In Great Britain December 10, 1930 12 Claims.

This invention consists in improvements in or relating to knittingmachines and has particular reference to yarn-feeding or splicing meansand to trapping or cutting devices therefor. The

invention isdesigned to be particularly applicable to machines in whichwarp-yarns are supplied to the needles in addition to other yarns fromground-yarn feeders or the like, but it is not limited to thisapplication. 1

The present invention comprises the combination of a yarn-feeder andactuating means therefor comprising an intermeshing rack and'pinion (ortoothed sector) one of which parts (e. g. the

pinion or sector) is operatively connected with '15. the feeder, and therack and pinion (or sector) are so formed that during endwise movementof the rack successive teeth thereon will be engaged with successiveteeth on the pinion (or 'sector).

Hitherto, a construction has been proposed in which on one side of thepivot about which a yarn-feeder was mounted to swing the end of thefeeder itself was bifurcated and a lip formed on a slider engaged in thebifurcation so that as the slider moved endwise the feeder was turnedabout its pivot. In such a construction a fine and accurate adjustmentof. the feeder to enable a close initial setting to be made isimpossible and, furthermore, backlash is unavoidable. By the presentinvention, however, the use of a rack and pinion (or toothed sector) inwhich successive teeth on the rack mesh with and engage suc- :cessiveteeth on the pinion (or sector) enables I In one form of the inventionin-lwhich two or more interchangeable yarn-guides are employed, there isa rack and pinion for each yarn,- guide and a single'locking means,common to all the racks, is employed to hold any one ofthem in aselected position (a. g. the position in which it has moved to itsassociated feeder to an 'operative position). Each rack when moved tothe selected position co-operates with the locking means so as first torelease it from a rack or racks held by it at that time and thereafterthe rack which thus releases the locking means is itself locked by thatmeans in the selected position.

The invention also includes a, yarn-trapping device with or without acutting device which, although it is particularly adapted for use withthe yarn-feeder mechanism above described, is not necessarily limitedthereto. Such a yarntrapper comprises in combination a pair ofyarngripping members resiliently held towards one I another and ayarn-catcher which is movable towards and away from the needles and isguided, on its movement away from the needles, between the yarn-grippingmembers. The latter members may be in the form of plates and in oneconstruction one member comprises two plates one behind the other for apurpose to be described hereinafter.

In order that the invention may be more clearly understood, a preferredexample will now be described with the aid of the accompanying l0drawings, in which-- Figure 1 is an elevation of a mechanism in cludingyarn-feeding, trapping and cutting devlces;

Figure 2 is a view looking from the left of Figure 1;

Figure 3 is a view looking from the right of Figure 1;

Figure 4 shows a detail of the device comprising yarn-feeders, theirassociated racks and the so locking device therefor;

Figure 5 is a schematic view illustrating the operation of the deviceand showing in addition a splicing yarn-feeder;

Figures 6 and '7 are perspective views illus- 35 trating parts only ofthe device to show clearly the operation of the trapper and cutter, and

Figures 8, 9, 10, and 11 illustrate diagrammatically in plan View themovement of the yarnoatcher relatively to the trapper-blades.

Like reference numerals indicate like parts in the several figures ofthe drawings.

In the form illustrated in the drawings the feeding means is constructedas an attachment to be applied to an existing knitting machine. Theattachment comprises a bracket having side plates 10 to which areattached an upper plate 11 and having lower extensions 12. Between theplates 10 is secured a spindle 13 on which a plu- V rality ofyarn-feeders 14 are pivotally mounted. Secured to each yarn-feeder so asto rotate with it is a pinion 15, and meshing with each pinion there isa sliding rack 16 there being as many racks as there are pinions. Theracks 16 are I formed as continuaticns of flat plates 17 which are allmounted to slide side-by-side between the side plates 10. The plates 17have abutments 18 arranged at different levels to be selectively engagedby'means of an adjustable external selector 19 between which and theracks there will be relative movement in the knitting direction. Theselector 19 is adjustable in height, under the control of any desiredpatterning device, e. g. a pattern control drum, so as to be moved atwill to engage any desired one of the abutments 18.

At the lower edge of each plate 17 there is formed a notch 20 to beengaged by the nose of a detent 21 which is urged always towards theedge of the plate by means of a coiled spring 22. The detent 21constitutes the locking means referred to hereinbefore. The back edge 23of each notch 20 is shaped to co-operate with the nose of detent 21, sothat as the plate 1'7 is moved to the left in Figure 4 by engagementwith the abutment 19, the edge 23 will first engage the nose of thedetent and will press it downwardly out of engagement with the notch ornotches 20 of any rack or racks held by it up to that time. When thisoccurs the rack or racks previously held are released and will return tothe position of the two plates 17 Whose tail-pieces 18 are farthest tothe right in Figure 4. Continued movement of the plate 17 that has thusreleased the detent 21, will permit the detent to snap intothe notch20of that plate so as to lock and hold the plate at the limit of itsmovement towards the left in Figure 4, and during this movement the rack16 of that plate will, by engagement with its co-operating pinion 15,move the associated yarn-feeder 14 from the inoperative position inwhich it extends upwardly to that in which it is operated and extendsdownwardly. The surface or edge 23 is at the end of a .recess 24 bywhich any plate, whengit is moved under the action of the selector 19.,

may slide almost to the full extent before tripping the .detent 21.

of the plates 17 is controlled by a compression spring 25 which exerts aspring pressure normally tending to move the plate to the inoperativeposition, that is, to the right in Figure 4. Each .spring is receivedpartly in a recess in the upper plate 11, one end of the spring engagingthe inner end of the recess, and the other end engaging an upstandingprojection 26 extending from its associated plate 17. The invention isnot limited to the spring-control of the plates 1'7, as they maybepositively returned, if desired,

from the operative to the inoperative position.

projector is in the form of aslide having a tail-- piece [28 whichextends in height over all the tail-pieces 18 so that each time one ofthe latter is moved by the selector 19, the latter will also engage thetail-piece 28 to move the pro-- the yam-projector 27 away from theneedles, that is, towards the right in Figure 1.

Attached to the main bracket of the device there is preferably a fitmentcomprising a bracket 31 held by screws 32 to the upper plate 11 andserving to support yarn-tensioning discs indioated generally by thereference numeral 33 and yarn-guides 34. Other yarn-guiding means shownas bent Wires 35 may also be secured to the brackets as indicated inFigures 1 and 2.

The yarn-trapper comprises a pair of gripping devices, one of which isin the form of a plate 36 and the other comprises two resilient strips37 and 38 having downwardly-projecting extensions 39 and 40,respectively. These extensions are situated slightly one behind theother for a purpose to be referred to hereinafter. The resilience of thestrips 3'7 and 38 serve to press them against the relatively rigid plate36 to afford the resilient yarn-gripping means. The strips 37 and 38 aresecured to one of the side plates 10 by means of set-screws 41, slots 42in the strips affording a means for adjusting the positions of theirextensions 39 ,and to obtain the best result.

The yarn-catcher comprises a slide plate 43 movable alongside, and incontact with the side plate 1 0 and this plate has adjustably secured toit by means of a screw 44, a resilient forwardly-directed extension 45.the outer end of which terminates in a hook 46 which can be seen mostclearly in Figures 6 and '7.

In order to guide the yarn-catcher or hook 46 the trapper-plateextensions 39 and 40 have their forward edges turned outwardly away fromthe companion trapper plate 36. In other words, the trapper plates haverelatively divergent edges presented towards the needles. The resilienceof the extension-piece 45 of the yarn-catcher tends to urge it towardsthe trapper-plates and away from plate 3.6. The upper edge of theextension-piece 451's .at alevel in the main below the lower extremitiesof the extensions 39 and 40 of the trapper. The forward portion of theextension-piece 45 which terminates in the hook 46 is, however, crankedupwardly above the level of the lower extremitiesof the extensions 39and 40, so that after the head and its extension-piece have been movedforward-1y, l. e. towards the needles, to its maximum extent, the rearvertical edge of the cranked extremity will-lie in front of the nip ofthe trapper--plates, whereby, when the yarn-catcher is withdrawn, itwill pass between the extensions 39 and 40--and the plate 36. It will beassisted in entering thus within the nip of the trapper owing to theoutward divergence of the forward edges of the extensions 39 and 40 withrespect to the plates 36. When the yarn-catcher has been retracted toits maximum extent, the position shown in Figure 1, the hook 46 will liein rear and clear of the trapper-extension 40, so that on the nextforward movement it will slide over the outer surfaces of extensions 40and 39, respectively, until the cranked .portion is again in advance of.the forward edge of the extension 39 in readiness for the nextretraction.

-The trapper-plate 36 is provided with a yarnguiding nose or hook 47beneath which the yarns will .be led'as they .are drawn into thetrapper. This ,nosejor hook serves to prevent accidental displacement ofthe .bight of yarn that extends between the trapper and a feeder that isin the inoperative. position.

.The yarn-catcher plate 43 terminates in a tailpiece .48 that canbeactuated by another pattern- 4, loo

controlled adjustable selector indicated in chain lines at 49 in Figure1.

The operation of the device illustrated and described above is asfollows: It is to be assumed that the yarn-feeder 14 shown in thelowermost position is that from which a yarn is at the moment ofconsideration being fed to. and taken by the needles, one of which isindicated at 50 in Figure 4. When it is required to replace that yarn byanother, the selector 19 is brought to the height of the tail-piece 18of the rack 16 that is associated with the feeder for the new yarn thatis to be introduced. As the selector and the tailpiece engage with oneanother during the relative movement between them, the sliding plate 17thus selected is moved to the left in Figures 1 and 4, andin so doingits rack 16 will turn the new feeder 14 anti-clockwise to bring it tothe position of the lowermost feeder indicated. Movement of the plate17, however, trips the detent 21 in the manner above described so thatplate 17 which, up to that time, had been locked by the detent, will nowbe released and returned to the right of Figures 1 and 4 under theaction of its controlspring 25. The plate 17 of the newly introducedfeeder 14 will, however, be locked by the detent 21 in the operativeposition in the manner already indicated. a

When the selector 19 operates to move one of ithe plates 1'7 tointroduce a new feeder into operation, the selector 49 also operates tomove the yarn-catcher 46 forwardly towards the needles into such aposition that the Withdrawn yarn will'pass into its hook as its feederis moved from 'i the feeding to the inoperative or upward position.

In this forward movement of the yarn-catcher it passes over the outsidesurfaces of the trapper extensions 39 and 40, and so does not disturbthe yarns already retained in the trapper. As soon I the withdrawn yarnis in the hook 46, the tailpiece 48 and selector 49 are disengaged andthe yarn-catcher moves back under the action of a tension spring 51, oneend of which is anchored at-52 to a side plate and the other end ofwhich Tis anchored at 53 to the plate 43.

Itrapper-plates into contact with the cutting edge of a fixed cutter 54adjustably secured by a screw' 55 passing through a slot 56 in thecutter and taking'into the side plate 11. The withdrawn yarn is thus cutand trapped, and it will be appreciated Ithat the construction ensuresthat the yarns already held within the trapper will not be accidentallyreleased, because, in the first place, that portion of the catcher-bladewhich passes between thetrapper-plates wipes over those yarns alreadytrapped, so that any unintentional disthe trapped yarns when the catcherfirst opens the foremost one 39. Before the rearmost one 40 is engagedby the catcher, the latter will itself have come into wiping engagementwith the trapped yarns so that even for a moment although both thetrapper members 39 and 40 may be the grip of the trapper.

When a thread is to be taken into operation, its appropriate feeder 14will be moved into the feeding position, and after the needles havecommenced to take the yarn the trapped end will be drawn out frombetween the trapper members.

The movement of the yarn-catcher relatively to the trapper-blades isdiagrammatically illus-' trated in Figures 8 through 11, considered inconjunction with Figures 6 and 7. In Figures 8 through 11, theprojecting head of the yarncatcher only is illustrated and it will beobserved that in the normal inoperative position, as shown in Figure 8,it is behind the trapper-blades 39 and 40 and so positioned that whenmoved forwardly towards the needles it will pass over the outside ofthose blades. Figure 9 shows the catcher moving to the left towards theneedles and passing over the outside of the blades as stated.Continuance of this movement brings the catcher to the position shown inFigure 10 and at this position it will engage the yarn that is to bewithdrawn. Its movement is then reversed and it will be observed thatthe catcher has assumed a position, due to the natural re-' silience ofthe blade 45, at which on its return stroke to the right it will enterbetween the trapper member 47 and the blades 39, 40 in succession, thefirst part of this movement being indicated in Figure 11. It will beseen that Fig ure 7 shows the catcher in a position interme-.

diate those of Figures 8 and 9 as it is moving towards the needles, andFigure 6 shows the catcher in substantially the position indicated byFigure 11.

There may, if desired, be combined with the mechanism hereinabovedescribed a splicing finger with its associated trapper and cutter. Onesuch arrangement is illustrated in Figure 5 in which the splicing fingeris indicated at 56 and the catcher-blades at 57. A yarn guide hook 58 isalso employed in association with the splicing finger in the manner andfor the purpose described in co-pending application Ser. No. 562,898.Alternatively, the splicing finger and cutter may be in the formillustrated in co-pending application Ser. No. 501,723.

The invention is applicable to circular knitting machines in which casethe attachment will be so disposed that sliding plates such as 17 and 43move substantially radially with respect to the needle and selector. Theinvention is not limited to this application, as it may be used withflat frame machines, in which case the sliding plates will move ina'direction substantially normal to a plane containing the needles.

Where it is stated in the specification and claims that the trappergripping members are resiliently held towards one another it is to beunderstood to include not only a construction alternative to thatillustrated, in which both members are resilient, but also that in whichonly one member is resilient as in the illustrated example.

I claim:-

1. In or for a knitting machine the combination of a yarn trappercomprising co-operating gripping members, a yarn catcher, means to movethe yarn catcher between the gripping members as it withdraws the yarnand means to move the yarn catcher along a different path as it isadvanced to engage theyarn.

2. In or for a knitting machine the combination of a yarn trappercomprising co-operating gripping members, a yarn catcher, means to movethe yarn catcher between the gripping members catcher on the outside ofone of the gripping members as it is advanced to engage the yarn.

3. In or for a knitting machine the combination of a yarn trappercomprising co-operating gripping members one of which comprises twoelements disposed one behind the other inthe direction of movement ofthe yarn catcher, a yarn catcher movable to engage the yarn and towithdraw it into the trapper and means to guide the yarn catcher betweenthe gripping members as it draws the yarn into the trapper.

4. In or for a knitting machine having a bed of needles and means tofeed the yarn to the needles, the combination of a yarn trappercomprising co-operating gripping members presenting divergent edgestowards the needles, a yarnv catcher movable towards and away from theneedles, means resiliently to urge the catcher towards a position atwhich when it is moved towards the needles so as to be clear of thegripper it will enter between the said divergent edges on its returnmovement, and means to guide the catcher to pass between the trappermembers as it withdraws the yarn but to travel along a dii' ferent pathas it is moved to a position to engage the yarn.

5. In or for a knitting machine the combination of a yarn trappercomprising co-operating gripping members whereof one is rigid and theother is resilient and by its resilience presses against its companionmember, a yarn catcher movable to engage a yarn to withdraw it betweenthe trapper members, means to move the catcher clear of the trappermembers in one direction to engage the yarn and to withdraw it betweenthe co-operating trapper members until it is clear of engagement betweenthem at the opposite end of its stroke, whereby on the return stroke itis free to pass over the outer surface of a trapper member.

6. In or for a knitting machine, the combination of a yarn trapper, ayarn catcher movable along one path to engage a running yarn and alonganother path to withdraw the yarn thus engaged to a position to becaught in the trapper and a yarn cutter presenting a cutting edge alongthe side of the cutter, the said cutting edge being in the path of theyarn to engage and cut the latter as it is drawn by the catcher into thetrapper.

'7. In or for a knitting machine having a bed of needles and means tofeed the yarn to the needles, the combination of a yarn trappercomprising co-operating gripping members one of which is resilientlypressed against another, a yarn catcher movable towards and away fromthe needles to be clear of one of said trapper members at both limits ofits movement, saidcatcher being normally urged to a position to -enterbetween the trapper members, means to move the catcher to engage theyarn and to withdraw it between the trapper members until it has beenmoved clear of the said trapper memher, a cutter situated to engage andout the yarn during movement of the catcher in withdrawing the yarnbetween the trapper members and means to advance the catcher againtowards the needles on the outside of the said trapper member cleared bythe catcher.

8. In or for a knitting machine the combination of a yarn trappercomprising cooperating gripping members resiliently urged towards oneanother and a yarn catcher which is movable towards and away from theneedles and is guided as it moves away from the needles between the yarngripping members, one of said gripping members comprising two plates orstrips disposed for the purpose described one behind the other in thedirection of movement of the yarn catcher.

9. In or for a knitting machine the combination of a yarn trappercomprising co-operating gripping members whereof one is in the form of aplate extending lengthwise in a direction towards the needles and has anextension projecting laterally therefrom between which and the companiontrapper member the yarn will be retained, and a yarn catcher in the formof a plate also extending lengthwise towards the needles and formed witha hooked extremity having a projection opposed to the lateral extensionof the gripper member to comprise with that lateral extensioninteracting portions such that on each stroke of the catcher to and fromthe needles the catcher will be moved clear of the trapper memher at theend of one stroke, but will engage it on passing during the reversestroke, and means to move the trapper member towards and from theneedles.

10. In or for a knitting machine having a pair of needles and means tofeed yarn to the needles, the combination of a yarn trapper comprisingco-operating members, a yarn catcher movable towards and away from theneedles, one of said trapper members being formed with a part extendingin a direction of movement of the catcher and another part extendingtransversely thereto to co-operate with the catcher and beingresiliently urged towards the companion trapper member, and thecompanion trapper member extends lengthwise in the direction of movementof the catcher to be engaged by the latter during the whole of itsyarn-withdrawing movement, and -means to move the catcher between thetrapper members as it withdraws the yarn and on the return stroke tomove it over the outer surface of the co-operating portion of theresiliently urged trapper member.

11. In or for a knitting machine having a pair of needles and means tofeed yarn to the needles, the combination of a yarn trapper comprisingco-operating members, a yarn catcher movable towards and away from theneedles one of said trapper members being formed with a part extendingin a direction of movement of the catcher and another part extendingtransversely thereto to co-operate with the catcher and beingresiliently urged towards the companion trapper member, and thecompanion trapper member extends lengthwise in the direction of movementof the catcher to be engaged by the latter during the whole of itsyarn-withdrawing movement, means to move the catcher between the trappermembers as it withdraws the yarn and on the return stroke to move itover the outer surface of the co-operating portion of the resilientlyurged trapper member, and a hook-like yarn guide extending towards theneedles from a portion of one of said trapper members that is adjacentthe needle bed.

12. In or for a knitting machine, the combination of a yarn-trappercomprising co-operating gripping members resiliently urged towards oneanother, ayarn-catcher which is movable towards and away from theneedles, and means to move the yarn-catcher between the gripping membersas it withdraws the yarn and along a different path as it is advanced toengage the yarn.

ROBERT HAROLD ROBINSON.

